1 1 Symposium Chemosensory Receptors Satellite DEVELOPMENT ...

197 Poster Multimodal, Chemosensory Measurement,Psychophysical, Clinical Olfactory, and TrigeminalODOR AND LATERALIZATION THRESHOLDS FORAMMONIA: A COMPARISON ACROSS STATIC ANDDYNAMIC OLFACTOMETRYSmeets M. 1 , Bulsing P. 1 , Ogink N. 2 , Van Thriel C. 3 , Dalton P. 4 1 UtrechtUniv, Utrecht, Netherlands; 2 A&F, Wageningen, Netherlands; 3 IFADO,Dortmund, Germany; 4 Monell Chemical Senses Center, Philadelphia,PALateralization thresholds (LT), in which irritancy is assessed by theability to localize to the stimulated nostril, have been used in the indoorair field in the context of setting occupational exposure limits. LT´s aretypically obtained using bottles (static olfactometry: SO) with singlechemical compound stimuli. However, if we wish to asses irritancy forcomplex mixtures, dynamic olfactometry (DO), in which odors arediluted in a clean air stream would be more appropriate. To this end, wecompared the performance of both methods using a single chemical,ammonia (NH3). Methods: Odor detection thresholds (ODT) and LT´sfor NH3 were collected using SO and DO (see above). A twoalternativeforced choice procedure was employed. 22 Females weretested on each method twice in a within-subjects design. Results: Forthe SO method, the (geometric) mean ODT = 2 (sem = 1.7), and LT =31 (sem = 1.3) ppm. For the DO method, the mean ODT = 2 (sem =1.2), and LT = 50 (sem = 1.3) ppm. There was no significant differencebetween methods (F < 1.0). Test-retest reliability was reasonable tohigh within methods (0.18 < r < 0.59) but low between methods (-0.09< r < 0.23). LT´s were significantly higher than ODT´s (p < 0.0001),thresholds measured at T=1 higher than at T=2 (p < 0.05). Conclusion:Both methods yielded very comparable mean results, and thus can beused interchangeably for estimates at the population level. However, onthe individual level, results should not be compared across methods.Funded by NWO 452-03-334198 Poster Multimodal, Chemosensory Measurement,Psychophysical, Clinical Olfactory, and TrigeminalIRRITATION, AMMONIA AND ASTHMAPetrova M. 1 , Diamond J. 1 , Schuster B.H. 2 , Dalton P. 1 1 Monell ChemicalSenses Center, Philadelphia, PA; 2 University of Dresden, Dresden,GermanySensitive subpopulations, such as those with asthma and otherrespiratory diseases, commonly attribute the exacerbation of asthmaticsymptoms to exposure to chemical odors and irritants. However, manyof the odors reported to cause asthma symptoms do not necessarilyreach concentrations capable of stimulating irritant receptors. The goalof the present study was to evaluate the irritation potential of ammonia(NH 3 ), and to determine whether there are any differences in nasal orocular irritant sensitivity between healthy individuals and those withmild-moderate asthma. 25 healthy and 15 mild-moderate asthmaticvolunteers (age 29.7 ± 10.8) were evaluated for their ability to detectodor and irritancy of NH 3 . Ammonia vapor was delivered to either sideof a set of specially-configured goggles (for the ocular exposure) or toeither nostril or both simultaneously for durations of 10 sec for thethresholds and up to 30 sec for the suprathreshold exposures.Additionally, 13 healthy and all asthmatic volunteers were evaluatedthroughout the testing sessions for pulmonary function usingspirometry. There were no significant differences in the sensoryirritation thresholds or rated intensity of irritation between asthmaticsubjects and healthy controls. Exposure to NH 3 didn´t alter pulmonaryfunction in either group. However, asthmatic individuals exhibitedsignificantly lower odor detection thresholds (93.24 ± 13.99 ppm,asthmatic, 153.35 ± 25.64 ppm healthy, P < 0.09). This implies that, insome instances, an adverse response to volatile chemicals amongasthmatics may be triggered by the perception of low-level odor, notirritation, and may reflect a psychogenically-mediated symptomresponse to a perceived health risk. Supported by NIH DC 03704 to PD.199 Poster Multimodal, Chemosensory Measurement,Psychophysical, Clinical Olfactory, and TrigeminalBREATHING RESPONSES OF NORMOSMIC AND ANOSMICINDIVIDUALS TO STIMULI PRESENTED IN ANENVIRONMENTAL CHAMBERWalker J.C. 1 , Walker D.B. 1 1 Sensory Research Institute, Florida StateUniversity, Tallahassee, FLTo investigate the effects of airborne contaminant exposures onbreathing in humans, we exposed 20 normosmics and 4 anosmics to 8conditions, each presented in 100-min sessions conducted in a 10m 3environmental chamber: environmental tobacco smoke (ETS) - 0, 15,100 and 800 µg/m 3 RSP; propionic acid (PA) - 0, 1, 10 and 15 ppm.Except with 15 ppm PA, for which the exposure plateau ended at min30, concentrations rose mins 11-20, were maintained through min 70and then declined. With normosmics, all PA concentrations caused amodest increase in inhalation duration (InDur). With the two lowest PAconcentrations, inhalation volume (InVol) was maintained whereas thisparameter declined slightly with 15 ppm PA and even more with cleanair. Thus, minute ventilation (MnVnt) was maintained over the courseof the session with 1 and 10 ppm PA while this parameter declined withclean air and, to a slightly less extent, with 15 ppm PA. With anosmicssmall increases and decreases, respectively, in InVol were seen with 1and 15 ppm PA. In normosmics, ETS increased InDur and decreasedInVol, resulting in a drop in MnVnt. Effects of ETS on anosmics werequite different. InDur was unchanged but InVol increased, with themagnitude of change following the order: 15>800>100 µg/m 3 . In theabsence of an InDur effect, the InVol pattern was repeated with theMnVnt parameter. This work will contribute to an improvedunderstanding of the principles underlying the integration ofchemosensory inputs, including ocular trigeminal, that yield changes inspecific breathing parameters under environmentally realisticconditions. Supported in part by the Philip Morris External ResearchProgram200 Poster Multimodal, Chemosensory Measurement,Psychophysical, Clinical Olfactory, and TrigeminalTEMPORAL INTEGRATION IN NASAL LATERALIZATIONOF ETHANOLWise P. 1 , Canty T. 1 , Wysocki C. 1 1 Monell Chemical Senses Center,Philadelphia, PATwo experiments examined how one can trade stimulus-duration withconcentration of n-ethyl alcohol to maintain a fixed level ofperformance in detection of nasal Irritation. Irritaiton threshold wasmeasured via nasal lateralization, a technique in which subjects receivechemical vapor in one nostril and clean air in the other. Subjects try todetermine which nostril received the chemical. Concentration was fixedwithin experimental runs, and stimulus-duration varied to find thebriefest stimulus subjects could reliably lateralize. Concentration variedbetween runs (1650 to 5000 ppm). Experiment 1 involved a small,intensively-tested group of subjects to obtain stable individual data.Experiment 2 involved a larger group and employed more rapidmethods. In both cases, a fixed-ratio increase in stimulus-duration couldcompensate for a fixed-ratio decrease in concentration. However, anincrease in duration of more the two-fold was required to compensatefor a two-fold decrease in concentration. These results suggest that asimple, but imperfect, mass-integrator model (i.e., an exponentiatedform of Haber´s rule) can describe short-term integration of nasallateralization of ethanol.50